export function  addClass(el,className) {
    if(hasClass(el,className)){
      return
    }
    let newClass=el.className.split(' ');
    newClass.push(className);
    el.className=newClass.join(' ');
}
export function hasClass(el,className) {
  let reg = new RegExp('(^|\\s)'+className+'(\\s|$)');
  return reg.test(el.className)
}
export function getData(el,name,val) {
      const prefix='data-'
      name=prefix+name
      if(val){
        return el.setAttribute(name,val)
      }else{
        return el.getAttribute(name)
      }
}
